Canon PowerShot G15 Review

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Canon PowerShot G15

Performance & Photo Quality

One of my big beefs with the PowerShot G12 (and the G1 X for that matter) was its mediocre performance. Thankfully, Canon has addressed that on the G15, promising a 53% reduction in focus times and a 45% reduction in "shooting time lag" (though I'm not sure what they mean by that). The table below summarizes its performance:

Timing

Measured Performance

How it Compares

Startup

1.4 sec

Average

Autofocus

0.2 - 0.5 sec (W)
0.4 - 0.9 sec (T)

Average

Autofocus
(Low light)

0.8 - 1.0 secs

Above average

Shutter lag

Not noticeable

Above average

Shot-to-shot
(JPEG, no flash)

~ 2 secs

Average

Shot-to-shot
(RAW, no flash)

~ 3 secs

Average

Shot-to-shot
(with flash)

~ 3 secs

Average

While both AF and shutter lag has been reduced on the PowerShot G15, it doesn't mean that it's suddenly a speed demon. As you can see, it's average in nearly all respects.

There are four full resolution burst modes on the PowerShot G15, though one of them (Continuous LV) is for manual focus and fireworks mode only, and will not be included below. That leaves us with regular continuous (locks AE/AF on first shot), continuous AF (adjusts focus and metering between each shot), and High-speed Burst HQ, a scene mode. Here's what kind of performance you can expect for each of those:

Image quality

Continuous

Continuous AF

High-Speed Burst HQ

RAW + Large/Fine JPEG

Unlimited @ 0.9 fps

Unlimited @ 0.6 fps

N/A

RAW

Unlimited @ 1.1 fps

Unlimited @ 0.7 fps

Large/Fine JPEG

Unlimited @ 1.9 fps

Unlimited @ 0.8 fps

10 shots @ 10.0 fps

Tested with a SanDisk Class 10 UHS-I SDHC card

First, the good news: the PowerShot G15 can keep shooting until your (high speed) memory card fills up, even with RAW files. There's no waiting for the buffer to clear, either -- you can enter playback mode or the menu right away. The bad news is that the burst rate isn't terribly impressive, especially if RAW images are involved. You can shoot faster using the High-Speed Burst HQ mode, though do note that it's only for JPEGs, limited to ten shots, and the ISO is set to "auto", so images may be noisy.

That does it for numbers, let's move on to some visual tests now!

Our macro test subject is looking very good here. The G15 produced a "smooth" rendition of the figurine, with vivid colors (and more importantly, no color cast under our studio lamps). There's no noise or detail smudging to be found, which is a good thing.

The PowerShot G15 has a pretty standard macro range for the enthusiast compact class. At full wide-angle, you can be just 1 cm away from your subject. The distances stay pretty low through most of the focal range until you get to around 4.5X, at which point the minimum distance jumps to 35 cm. At full telephoto, the minimum focusing distance is 40 cm.

Our night shot is a little special in this review, with many of the buildings lit up in orange, to celebrate the San Francisco Giants' victory in the World Series. The photo quality looks good here, with highlight clipping being the only issue that I could find. With manual control over shutter speed, bringing in enough light is easy (you should be able to get similar results with Smart Auto or scene modes). One of the G15's faults is that it clips highlights frequently, and that's on full display here. The buildings are nice and sharp, and there are no funny color casts here either. Noise is not an issue, and purple fringing is minimal.

Normally I like to show you how the camera performs in low light across its ISO range. Unfortunately, Canon won't let me do that. As on some of their other recent cameras, they lock the ISO at 80 if the shutter speed is below 1 second. That makes sense from an image quality point-of-view, but putting such limitations one of their flagship cameras (especially in "M" mode) is as dumb move on Canon's part. So, the example below picks up at ISO 800:

ISO 800

ISO 1600

ISO 3200

ISO 6400

ISO 12800

I was impressed with how well the PowerShot G15 performed at ISO 800 in this night scene. Sure, there's some noise and detail smudging, but it's not bad enough to prevent you from making a mid-sized or perhaps larger print. Detail loss is more noticeable at ISO 1600, so this is a good place to stop if you're shooting JPEGs, or try switching to RAW. I'd probably avoid the ISO 3200 setting in low light unless you're shooting RAW (more on that below), and would skip ISO 6400/12800 altogether.

I will add a RAW vs. JPEG comparison as soon as Adobe releases a version of their Camera Raw plug-in that is compatible with the PowerShot G15.

Straight out of the camera, both redeye reduction features turned on

After a trip through the redeye correction tool in playback mode

The PowerShot G15 tries to eliminate redeye in two ways. First, it'll fire the AF-assist lamp a second or so before the photo is taken, with the goal of shrinking your subject's pupils. I've found that this rarely works. The second part of the removal system is a digital system (which needs to be turned on in the Flash Settings menu), which tries to get rid of whatever shows up in a photo. As you can see, neither of those methods worked. All is not lost, though -- there's a removal tool in playback mode that was able to get rid of the red, so definitely try that if your flash photos have redeye.

There's very little barrel distortion at the wide-angle end of the PowerShot G15's 28 - 140 mm lens. That's probably because that Canon, like most manufacturers, is digitally correction for it as you take a photo. The G15's lens is definitely a quality one, with no corner blurring or vignetting to be found.

Okay, now it's time to see how the PowerShot G15 performed across its ISO range in normal light. As usual, I'm using our standard studio test scene, which means that you can compare the results with other cameras I've tested over the years. Remember that the crops below only show a small area of the total scene, so view the full size images too!

ISO 80

ISO 100

ISO 200

ISO 400

ISO 800

ISO 1600

ISO 3200

ISO 6400

ISO 12800

Everything looks great through ISO 800, with very little noise or detail loss to be found. Noise finally shows up at ISO 1600, but it's so minor that you can make large prints without a problem at that sensitivity. Noise levels increase at ISO 3200, and this is my recommend stopping point for JPEGs shooters. That's because of the moderate noise levels at ISO 6400, which we may be able to knock back with RAW. I'd avoid ISO 12800 altogether -- once again, I don't know why camera companies even bother putting these unusable sensitivities on their cameras (marketing, most likely).

As I said in the night shot discussion, I cannot perform my RAW vs. JPEG comparison yet, due to the lack of an updated Adobe Camera Raw plug-in. As soon as one becomes available, I will update the review.

Lots of PowerShot G15 buyers are undoubtedly comparing it against the new Nikon Coolpix P7700 and Panasonic Lumix DMC-LX7. So, I decided to put together a comparison of the JPEG image quality at ISO 1600 and 3200 for all three of those cameras. Two quick notes before we go on:

I used JPEG instead of RAW here because 1) I can't convert G15 RAW images yet and 2) using JPEG at default settings levels the playing field, due to all the variables in RAW conversion

The colors in the Nikon images are really flat compared to the other two cameras. I guess it doesn't like my studio lamps. Remember that we're comparing noise here, and not color accuracy.

It's pretty obvious that the PowerShot G15 was the winner here, at least when using the JPEG format. The other two cameras may be able to match or exceed the image quality of G15 by using RAW, but as I said above, RAW opens up a whole other can of worms. The bottom line here is that the PowerShot G15 produces some very impressive images for a camera with a relatively small sensor.

The PowerShot G15 does so many things right when it comes to image quality that its hard to find much to complain about! Exposure was almost always accurate, so you shouldn't need to bracket your shots. The G15's biggest IQ flaw is that it loves to clip highlights. I am a big fan of the DR correction feature for this very reason, and am willing to accept the increase in noise for the decrease in HL clipping. Colors are really punchy, and sharpness is just how I like it. As you've seen in the various tests above, the G15 keeps noise levels low through ISO 800 in low light, and ISO 1600 in low light -- and that's for JPEGs. Purple fringing levels were low, which is another testament to the quality of the G15's lens.

Now it's time for you to evaluate the PowerShot G15's photo quality with your own eyes. Open up our extra large photo gallery, view the images at 100% (and maybe print a few), and then decide if the G15's image quality meets your needs!